1. Field of the Invention
The present invention relates generally to a mounting apparatus for removable attachment of a float blade or a combination blade to a blade assembly of a trowel.
2. Description of the Related Art
Generally, motor-powered trowels include a rotary blade assembly which engages, packs and finishes concrete, cement and the like. The blade assembly may include float blades or combination blades removably secured to each finishing blade of the blade assembly.
In conventional practice, newly poured concrete or cement is first worked with float blades, to smooth the concrete surface and achieve a uniform appearance. Simultaneously, the floating operation settles large stones and causes fine particles to rise to the surface. Thereafter, the float blades are removed from the blade assembly. The concrete then is finished with finishing blades which are standard equipment on most trowels. Conventional float blades are constructed from abrasion-resistant steel. The use of removable float blades increases the life of the finishing blade assembly. Reversible float blades are known but have not come into widespread usage.
Alternatively, a combination blade can be removably attached to the trowel blade assembly. The combination blade is utilized for both the floating and finishing operations.
Various systems have been devised to quickly mount a float blade or a combination blade on a trowel blade assembly. Prior art methods are described in the following representative U.S. Pat. Nos. 2,556,983; 2,662,454; 2,689,507; 2,865,269; 2,888,863; 2,999,261 and 3,375,766.
The art continues to seek improvements. It is desirable that a float blade or a combination blade be readily and removably mountable on a trowel finishing blade. It is desirable that a mounting system be economical to install, easy to operate and adaptable for either float or combination blades.
The present invention relates to a blade construction and to an apparatus for removably mounting a blade on a finishing blade of a trowel. The mounting apparatus is economical to install, easy to operate and adaptable for either a float blade or a combination blade. The blade construction of the invention further relates to float blades and combination blades employing the present mounting apparatus.
In a preferred embodiment, the present mounting apparatus includes a pair of retaining tabs secured to an upper surface of a blade adjacent leading corners. Each retaining tab includes a side wall, an end wall and a cover plate which forms a cavity with the blade upper surface. A second pair of retaining tabs are secured to the upper surface of the blade adjacent trailing corners. The four retaining tabs cooperate to removably secure the blade to a trowel finishing blade without the use of mechanical fasteners.
In an alternative embodiment, at least one stop element replaces the trailing retaining tabs to secure a blade on a trowel finishing blade.